Have you seen a bunch of these in your house? Do you have what you thought might be termintes only to discover that termite treatments don’t do much to battle the infestation? If so, you likely have an infestation of psocids. These tiny little insects are also known as booklice and barklice and are known to feed on old books and other natural materials. It’s rare to have them infest a straw bale house, but it can happen. In most, if not all cases of home infestation, the insects come in on the bales and are already in the straw when you build your house. They take a relatively high level of moisture to live and so keeping your bales dry will almost always end any infestations. Here’s some more information about these insects, how to stop an outbreak, and how to minimize your risk of infestation to start with.
Psocid infestations typically more prevalent in areas with high moisture content and which are often contaminated with microscopic mold. The psocid’s life cycle includes eggs, four nymphal stages, and adult females. Eggs usually take about 21 days to hatch and adults tend to live for between 20 and 100 days. This puts an entire lifecycle somewhere between 40 and 120 days. The sooner you discover an infestation and start to take action the better as females can each lay up to 2 eggs a day during their adult life. That’s a reason for the sudden outbreaks most often noted.
The best way to handle an existing infestation is to dry out the space in question. The psocids take a high level of moisture to survive and so a dry and hot space will quickly solve the problem. Because of the number of eggs that each female can lay, you’ll need to keep the location hot and dry for at least 4 months to be sure of total removal of the problem. It has been said that bringing a room to 120 degrees F for a short period of time can also kill the insects completely. The challenge is getting that 120 degrees F to reach the internal sections of the bale walls as the insulation value is what is so loved about these homes. As we’ve seen in fire testing, it is not easy to transfer high or low temperatures through a bale wall and so the likelihood of achieving a sustained 120 degrees F in the center of a bale wall is low.
To lower your risk of ever getting an infestation I suggest you treat your bales during installation with borax. Just a gentle sprinkle of borax on each course of bales during installation can be very helpful for eliminating any pest problems. I want to be clear here, I have only twice seen this situation actually happen in a bale structure and I do not use borax on any of the homes I build. I make the suggestion only for those homes that are at high risk. For example, homes that will likely experience high moisture levels in the walls due to a lack of dehumidifying system and high relative humidity in the environment. Otherwise, I don’t think the borax is necessary.